How to lay felt on a flat roof
A flat roof is a popular choice for many homeowners due to its affordability and versatility. While flat roofs require regular maintenance and occasional repairs, one important step in their installation or repair process is laying felt. Felt acts as a protective layer against moisture, ensuring the longevity and durability of the roof.
Laying felt on a flat roof may seem like a daunting task, but with the right tools and technique, you can successfully complete this project. This article will provide you with a step-by-step guide on how to lay felt on a flat roof, ensuring a watertight and secure finish.
Step 1: Prepare the roof
Before laying felt, it is essential to prepare the roof surface. Clear any debris, dirt, or loose materials, and make sure the roof is clean and dry. Inspect the roof for any cracks, holes, or damage, and repair them before proceeding. A smooth and flat surface is crucial for laying the felt properly.
Tip: It’s important to wear appropriate safety gear, such as gloves and safety glasses, when working on a flat roof.
Preparing the roof surface
Before laying felt on a flat roof, it is important to properly prepare the roof surface. This involves a few important steps:
Clean the roof: Start by thoroughly cleaning the roof surface of any debris, dirt, or loose material. Use a broom or a brush to remove any loose dirt or debris, and a pressure washer or hose to remove any built-up dirt or moss. It is essential to have a clean and smooth surface before laying the felt.
Check for any damage: Inspect the roof for any signs of damage, such as cracks, holes, or loose or missing tiles. Repair any damages and ensure that the roof is structurally sound before proceeding with the felt installation.
Apply a primer: Applying a primer to the roof surface is a crucial step to ensure proper adhesion of the felt. The primer helps to create a suitable surface for the felt to bond to and also helps to seal any porous areas. Follow the manufacturer’s instructions on how to apply the primer and allow it to dry completely before proceeding.
Note: It is essential to choose a primer specifically designed for flat roofs and compatible with the type of felt being used.
Measure and cut the felt: Get accurate measurements of the roof dimensions and cut the felt accordingly. Typically, it is recommended to have an overhang of at least 2 inches on all sides to ensure full coverage and to allow for proper drainage of water.
Lay the felt: Start laying the felt from one end of the roof, ensuring it is straight and aligned with the edges. Secure the felt in place using roofing nails or adhesive, following the manufacturer’s instructions. Overlap each strip of felt by at least 4 inches to prevent water penetration.
Note: It is important to work in small sections, applying the adhesive or nails as you go, to ensure proper installation and prevent the felt from shifting.
Seal the edges: Once the main area of the roof is covered with felt, it is important to seal the edges. This can be done using a sealant or flashing tape, applied along the edges and any joints or corners, to provide a watertight seal and prevent any leakage.
Inspect and maintain: After the felt is properly laid on the roof, conduct a final inspection to ensure there are no loose areas or visible damages. It is also important to regularly inspect and maintain the felt roof to prolong its lifespan and prevent any potential issues.
Applying the primer
Before you start applying the felt, it is important to prepare the roof by applying a primer. The primer helps improve the adhesion between the roof surface and the felt, ensuring a strong bond.
Step 1: Clean the roof surface
Begin by cleaning the roof surface thoroughly. Remove any loose debris, dirt, or vegetation. Use a stiff brush to sweep the surface clean. Ensure that the roof is completely dry before applying the primer.
Step 2: Choose the right primer
Select a primer that is suitable forthe type of roof you have and the type of felt you will be using. Check the manufacturer’s instructions for guidance on the correct primer to use.
Step 3: Apply the primer
Apply the primer to the roof surface using a roller or a brush. Start at one end of the roof and work your way across, following the manufacturer’s instructions regarding the application rate and coverage. Ensure an even coverage, avoiding any puddles or pooling of the primer.
Allow the primer to dry completely. This typically takes anywhere from a few hours to overnight, depending on the type of primer and the weather conditions.
Once the primer is fully dry, it is ready for the next step – laying the felt on the roof.
Measuring and cutting the felt
Before laying the felt on your flat roof, it is important to measure and cut it accurately to ensure proper coverage and a tight fit. Here are the steps to follow:
- Start by measuring the length and width of your roof using a measuring tape. Ensure you take accurate measurements to avoid any wastage or gaps in the coverage.
- Next, transfer the exact measurements onto the felt using a pencil or marker. Use a straight edge or ruler to create straight lines.
- Once you have marked the measurements, carefully cut the felt along the lines using a utility knife or a pair of sharp scissors. Make sure to use a cutting surface such as a cutting mat or a piece of plywood to protect your work area.
- When cutting the felt, it is recommended to add an extra inch to each side. This additional allowance will ensure that the felt drapes over the edges of the roof, providing extra protection against leaks.
- When cutting around roof protrusions such as vents or chimneys, measure their dimensions and mark them on the felt. Cut slits or openings into the felt to fit snugly around these obstacles.
- Repeat the measuring and cutting process for each piece of felt needed to cover the entire roof. Remember to label each piece to ensure easy installation later.
By taking accurate measurements and cutting the felt precisely, you can ensure that it fits perfectly on your flat roof, providing it with the necessary protection against weather elements.
Applying the felt sheets
Once the flat roof surface has been prepared and the necessary materials gathered, it is time to start applying the felt sheets. This step is crucial in ensuring a waterproof and durable roof.
1. Start at one end: Begin by rolling out the first sheet of felt at one end of the roof. Make sure to align it properly with the edge of the roof.
2. Secure the felt: To secure the felt in place, use a hammer or a staple gun to attach roofing nails or staples along the edge of the felt sheet. Space them out accordingly, following the manufacturer’s recommendations.
3. Overlap the next sheet: Roll out the next sheet of felt, making sure it overlaps the previous one by at least 50mm (2 inches). This will help ensure water doesn’t seep through the joints.
4. Secure the overlapping section: Apply adhesive or use roofing nails/staples on the overlapped section of the two felt sheets to ensure they are secured together.
5. Repeat the process: Continue rolling out and overlapping the felt sheets, securing them with adhesive or nails along the way. Make sure to check that the sheets are laid flat and free of any wrinkles or bubbles.
6. Cut the excess: Once the entire roof surface is covered with felt sheets, trim off any excess material using a utility knife or shears. Be cautious when cutting and ensure a straight edge.
7. Secure the edges: Finally, nail or staple the edges of the felt sheets to secure them tightly in place. This will help prevent any lifting or water damage in the future.
TIP: It is essential to follow the specific instructions provided by the felt manufacturer, as they may have additional recommendations or requirements for installation.
Securing the felt
To ensure a secure and watertight application, it is important to properly secure the felt to the flat roof surface. Here are the steps to follow:
- Start by positioning the first layer of felt at the edge of the roof, ensuring that it overhangs the edge by a few inches. This will prevent any water infiltration.
- Apply a generous amount of felt adhesive to the roof surface using a brush or a trowel. Work from one end of the roof to the other, making sure to evenly coat the surface.
- Place the first layer of felt onto the adhesive, aligning it with the edge of the roof. Gently press it down to ensure good adhesion.
- Continue applying adhesive and laying felt in the same manner, overlapping each strip by a few inches to create a waterproof seal. Stagger the joints to improve the overall durability.
- When reaching obstacles such as skylights or vents, cut out a section of felt to fit around them, ensuring a snug and secure fit. Apply adhesive to both the surface and the back of the cut-out section before placing it in position.
- Once all the layers of felt have been laid, use a seam roller or a hand roller to firmly press down the edges and joints. This will help to ensure a tight and secure bond.
- Finally, allow the adhesive to fully cure and dry according to the manufacturer’s instructions before proceeding with any further roofing work.
By following these steps and ensuring proper adhesion, you can ensure a professional and long-lasting felt installation on your flat roof.
Harrison Clayton
Meet Harrison Clayton, a distinguished author and home remodeling enthusiast whose expertise in the realm of renovation is second to none. With a passion for transforming houses into inviting homes, Harrison's writing at https://thehuts-eastbourne.co.uk/ brings a breath of fresh inspiration to the world of home improvement. Whether you're looking to revamp a small corner of your abode or embark on a complete home transformation, Harrison's articles provide the essential expertise and creative flair to turn your visions into reality. So, dive into the captivating world of home remodeling with Harrison Clayton and unlock the full potential of your living space with every word he writes.
